The intermediate formed during the addition of HCl to propene in the presence of peroxide is

Options

A. `CH_3overset.CHCH_2Cl`
B. `CH_3overset+C HCH_3`
C. `CH_3CH_2overset.CH_2`
D. `CH_3CH_2overset+CH_2`

Answer

To determine the intermediate formed during the addition of HCl to propene in the presence of peroxide, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The reactants are propene (C3H6) and HCl, with the presence of peroxide (like hydrogen peroxide, H2O2).

2. **Understand the Role of Peroxide**:
- In the presence of peroxide, the addition of HCl to alkenes follows a different mechanism known as the radical mechanism. This is due to the formation of free radicals.

3. **Formation of Hydroxyl Radicals**:
- Peroxide undergoes homolytic fission to produce hydroxyl radicals (•OH). For example, H2O2 can break down to form two •OH radicals.

4. **Generation of Chlorine Radical**:
- The hydroxyl radical can react with HCl, leading to the formation of a chlorine radical (•Cl) and water (H2O). The reaction can be represented as:
\[ •OH + HCl \rightarrow •Cl + H2O \]

5. **Addition of Chlorine Radical to Propene**:
- Propene (CH3-CH=CH2) has a double bond, which is reactive. The chlorine radical (•Cl) can add to one of the carbon atoms in the double bond. Given that the radical is highly reactive, it will preferentially bond to the carbon that has more hydrogen atoms (following the Anti-Markovnikov rule).

6. **Formation of the Intermediate Radical**:
- When the chlorine radical adds to the terminal carbon of propene, it results in the formation of a secondary radical:
\[ CH3-CH(•Cl)-CH2 \]
- This radical is a secondary radical because the carbon bearing the radical is attached to two other carbon atoms.

7. **Conclusion**:
- The intermediate formed during the addition of HCl to propene in the presence of peroxide is a secondary radical, specifically:
\[ CH3-CH(•Cl)-CH2 \]

### Final Answer:
The intermediate formed is a secondary radical: **CH3-CH(•Cl)-CH2**.

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